1. Field
The present application relates to wireless systems, and more specifically to systems, methods and apparatus configured to manage neighbor cell lists in wireless systems.
2. Background
Wireless communication systems are widely deployed to provide various types of communication (e.g., voice, data, multimedia services, etc.) to multiple users. In addition to mobile phone networks currently in place, a new class of small base stations has emerged, which may be installed in a private or public spaces to provide wireless coverage to mobile units using broadband Internet connections. These small base stations are generally known as access point base stations, or, alternatively, Home Node B (HeNB or HNB) or femto nodes. Typically, femto nodes are connected to the Internet and the mobile operator's network via a direct subscriber line (DSL) router or a cable modem. Femto nodes may be deployed by individual users or groups within the coverage area of a conventional macro node or cell.
In order to enable user devices to transfer service from one base station or access point to another, various wireless network standards enable base stations and access points to provide deployment information to user devices. Typically the deployment information is a list of neighbor cell identifiers known as a neighbor cell list (or a neighbor list).
However, according to some wireless network standards, such as Universal Mobile Telecommunication System (UMTS) for example, the size of the neighbor list is restricted to a maximum size. That is, a base station or access point can only include a preset number of neighbor cell identifiers in the neighbor list at one time. The fixed size of a neighbor list provided by a standard may not reflect the realities of a wireless network deployment, especially for deployments including numerous femto cells clustered in close proximity. In particular, the number of macro, pico and/or femto cells in one area may exceed the maximum size of the neighbor list as specified in a standard relevant to the deployment. Accordingly, as the concentration of macro cells and/or femto cells in an area increases, there lies a challenge to identify and communicate neighbor lists to user devices that reflect the arrangement of a particular portion of the deployment and the needs of the user devices.